Mechanism for protecting thread shearing revolvers



M y 1945- w. IL. LAFOND 2,374,821

MECHANISM FOR PROTECTING THREAD SHEARING REVOLVERS Filed Dec. 4, 1943 4 Sheets-Sheet l w Zea .llafoncl,

zweni'on- May 1, 1945- v w. L. LAFOND T 2,374,821

MECHANISM FOR PROTECTING THREAD SHEARING REVOLVERS Filed Dec. 4, 1943 4 Sheets-Sheet 2 W .y 44. 5 (A'Q? NUT g? Q a R m as Q Q j Leo 998230 y 1, 9 w L. LAFOND 2,374,821

MECHANISM FOR PROTECTING THREAD SHEARING REVOLVERS Fi-led Dec 4, 1943 4 Sheets-Sheet 3 Waae Leo Lyo3zd, 1220822303 vii/303 27439 May 1, 1945. w. L. LAFOND MECHANISM FOR PROTECTING THREAD SHEARING REVOLVERS 4 Shets-Sheet 4 Filed Dec. 4, 1943 Patented May I, 1945 MECHANISM FOR PROTECTING THREAD SHEARING REVOLVERS Willie Leo Lafond, Woonsocket, R. I., assignor to Manville Jenckes Corporation, Manville, R. 1., a corporation of Delaware Application December 4, 1943, Serial No. 512,990

7 Claims This invention relates to mechanism for protecting thread shearing revolvers. More particularly it provides mechanism for detecting pieces of metal in a travelling web of cloth and then displacing the revolver and the web rela-- tively to permit the piece of metal to pass the revolver without contacting it and thus without danger of damage being done to the revolver by the piece of metal.

Thread shearing revolvers are expensive as to first cost and are expensive to recondition when a cutting edge becomes nicked or otherwise damaged. Yet any slight nick or imperfection in a cutting edge necessitates such expensive reconditioning of the revolver because the imperfection in the cutting edge produces an imperfection in the sheared cloth. It is important therefore to protect the revolver against contact with pieces of metal which not infrequently get into the cloth. A needle or a metal fragment accidentally may find its way into the cloth and pass unobserved to the shearing region. r If the revolver and cloth continue in shearing relation when the metal passes, the result almost certainly will be a damaged revolver. In addition to the cost to recondition such a damaged revolver, there is involved a loss of time and labor while a new or reconditioned revolver is substituted for the damaged one.

It is an object of my present invention to avoid the possibility of pieces of metal being carried in a web of cloth into contact with the thread shearing-revolver, thus ensuring against injury to the revolver from this source.

Another object is to combine my revolver protecting mechanism with a seam protecting mechanism in a manner to utilize many parts in common, the two said protecting mechanisms being connected in parallel in an electric circuit which is responsive both to a detected cloth seam and a detected piece of metal in the cloth.

A feature is that the revolver protector may be in the form of an attachment which simply and economically may be applied to already installed thread-shearing machines. 1

Still another object is to employ a multiple plate contact metal-detector unit designed todetect any piece or particle of metal having size capable of nicking a cutting edge of a, revolver by contact therewith.

The mentioned objects and results are attained by providing in a machine having a revolver for shearing threads of cloth means actuated by a piece of metal covered by the cloth and capable to of displacing the revolver and cloth relatively out of thread-shearing relation, maintaining them out of such relation during a predetermined time interval, and permitting their return to shearing relation at the expiration of the interval. Combined therewith, at a predetermined distance in advance of the shearing position, I provide a bank of separated electric contacts over which the strip of cloth passes on its course to the shear. The contacts, closely associated with thin insuiation between them extend throughout the breadth .of the cloth strip and each of alternate ones of the contacts constitues a terminal of an open circuit to electrically operated means for causing relative movement of the revolver and cloth.

-Each of the others of the contacts constitutes a second terminal of that open circuit. onsequently, if a piece or fragment of metal in the cloth bridges across any adjacent two of the con" tacts, the circuit will be closed to initiate relative displacement of the revolver and cloth at the shearing position.

Spaced slightly away from the bank of contacts as above described is a plate between which and shearing relation, while the detected seam passes.

The best mode in which I have contemplated applying the principles of my invention is shown in the accompanying drawings, but these are be deemed merely illustrative because it is in tended that the patent shall cover, by suitable expression in the appended claims, whatever features of patentable novelty exist in the invention disclosed. a

In the accompanying drawings:

Figure 1 is an end elevation ofa float thread shearing machine embodying features of'my invention;

Figures 2 is a similar view of the upper part of Figure 1, on a larger scale, the right hand por- 1tio of the view being in medial vertical secion;

Figure 3 is a top plan of the detector mechanism of Figures 1 and 2 with the guide roll and the cloth omitted for clearness of showing;

Figure 4 is a detail vertical sectional view on 6-4 of Figure 3, on a larger scale;

Figure 5 is an end view, looking from the left in Figure 1, showing the mechanism for actuating the shear-carrying frame, portions being in vertical section;

Figure 6 is a diagrammatic view of the electrical circuits; and

Figure 7 is an elevation of the latch-actuating mechanism of the control switch, the supporting wall being in section.

Referring to the drawings, my invention is shown applied to a float thread shearing machine. As best seen in Figure l, a strip of cloth I travels in the direction of the arrows around the guide rolls I2, It, I6 and 98 to the usual fixed cloth rest 28 at the shearing position, whence, after being acted upon by the shear, it passes down and around guide rolls 22, 2 3, 26, 28 and 36, to be eventually wound up as a roll. The guide rolls and the cloth rest 22 are suitably mounted on the frame of the machine, indicated generally at 32, 341. Guide roll 25 is power driven and constitutes the means for drawing the web It through the machine. It may be driven by a suitable connection from the main shaft 38 which in turn may be driven from any suitable source of power.

The run of the cloth between guide rolls it, It passes between presser element 38 and a rotary brush it on shaft 32, the element Sdengaging the cloth from the rear and the brush acting on that side of the cloth .having the float threads, to condition the threads for the shearing operation. Brush shaft 32, suitably mounted on frame 32 as at 4% (Figure 2) is driven from shaft 26, but in opposite direction, by means of the crossed belt 56 trained over pulleys 38, Ell and 52, the first two being on shafts 36 and 42 respectively, and pulley 52 being an idler.

The shearcomprises a usual revolver 55 coacting with a usual shear blade 56 (Figure 2) which is fixed relative to the revolver. As herein represented, both the revolver 54 and the blade 56 are mounted on the tiltable frame 58 which is pivoted at 50 on the fixed frame part 3 3 of the machine. The revolver is driven from shaft 36 through the belt andpulley drive connections 62, 6t and 66.

A lever 68 is pivoted at III on the frame 32 of the machine and has one end engaging the lower end of the revolver carrying frame 58. The other end of lever 68 carries aroller 32 which rides on the periphery of a cam It (Figures 1, Zand which is free on the projecting shaft 2'! of constantly rotating guide roll 26, as best seen in Figure 5. A spur gear 16, also free on the shaft 2?, is secured to the cam as by screws I8 (Figure 5) and meshes with one spur gear 80 of an integral pair 80, 82 on an underneath shaft 8%. The other spur gear 82 of the integral pair meshes with a spur gear 86 which is free on shaft 2! and has a clutch face 88++ adapted for coaction with a clutch element 90 which is slidably keyed as at 92 on shaft 27. Hence, when the rotating clutch element 90 is shifted into engagement with the clutch face 88 of gear 86, cam It rotates and its high side elevates the roller end of lever 68 and depresses its other end to rock the shear carrying frame 58 counterclockwise about its pivot 60, thereby to swing the revolver 54 and shear blade 56 away from shearing relation to the cloth II] where it passes over the cloth rest 20. When roller I2 on lever 68 rides from the high to the low side of cam I4, the shear frame 58 is permitted to resume its normal position under the l a seam is approaching the revolver.

-As best seen in Figures 3 and 4, the cloth Ill passes vertically between a plate 94 and a bank of contact elements 98 indicated generally at 96.

of the machine.

Both plate 9 3 and the elements 96 have length.

approximately equal to the width of the cloth strip, as seen in the plan view of Figure 3, and the space between them approximates the thickness of the cloth Ill. The plate 92 is actuated by a seam II to effect displacement of the revolver, whereas the contact elements 96 are depended upon to detect a piece of metal and bring about the displacement of the revolver.

Plate 9% is yieldable in direction away from the bank of elements 96 so that a seamattempting to pass between them must displace plate 94 to the left (Figures 1, 2 and 4) in order to pass. Such a displacement of plate 95 by a seam per mits a presser element 98 (Figure 3) to follow it with the result that an electric switch indicated generally at Illll, which normally is held open, is permitted to close, thereby to close an electric circuit through solenoid I02 (Figures 1, 2 and 6), which initiates actuation of clutch element into driving relation with clutch face 82 of gear 86 to cause rotation of cam I4, rocking of lever 58 and counterclockwise movement of the shear-carrying frame 58.

Th bank of contact elements indicated enerally at 98 and between which and plate 913 the cloth ID passes on its approach to guide roll I8 comprises a series of metal plates I26, I28 alternately arranged in multiple above and below a contact elements may be mounted on the frame Thin sheets I32 of insulation material separate the plates I26, I28 from each other, and the plates and insulation sheets are clamped together and to the supporting element E30 by bolts I34, one at each end of the bank or stack and each havin a nut I36 on its opposite ends. Each bolt I36 extends through all of the elements of the stack and has a surrounding insulatingbushing I38 maintaining it out of electrical contact with all of the plates I26, I28. The bushing at its lower end has an integral flange I39 intervening between nut I36 and the lower plate, and an insulating strip M0 intervene between the upper nut I35 and the top plate and carries the terminal screws I42. All.

of the plates I26 are electrically connected together, and all of the plates I28 similarly are electrically connected together. Figure 6 suggests the electrical interconnection of the individuals of both sets of plates, where thin U-strips I44 of metal bridge from one plate I26 to the next plate I26 in the stack and the bridges of the U-strips are shaped to contact each other, and likewise tecting mechanism heretofore described. Hence. whenever a metal piece or fragment in thecloth ization of solenoid II2.

l bridges two of the metal plates I28, I28, the circuit through the solenoid I02 is closed in the same manner that the relay circuit is completed when a seam is detected and switch I00 is closed. Accordingly in what follows, the resulting action following the energization of solenoid I02 is the same regardless of whether a seam or a piece of metal is detected.

The energization of solenoid I02 causes a le ver I03 (Figure 7)- to swing to the left and pull a rod'IIS with it. This rod passes somewhat loosely through a hole in the lower end of a latch bar I I8 that has loose pivotal connection with a switch lever- I22 at I23. On the latch bar H8 is a latch I24 which normally engages the switch lever I22 and holds the latter in such a position that a snap switch H4 is kept open. When the rod H9 is pulled by lever I03 upon energization of solenoid I02, the bar H0 is also swung to the left releasing latch I24 from the lever I22 which thereupon swings to the right. as seen in Figure 2, to close switch I I4.

This completes a circuit through a solenoid I I2 and causes an armature rod IIO (Figure to be drawn upward and swin a bell crank lever I08 about its pivot I09. The bell crank is pivotally connected at I01 to one end of a lever I04 which is pivoted at I05 and has its other end engaging the clutch element 90. Accordingly energize.- tion of solenoid M2 effects the movement of clutch element 90 into engagement with the other clutch element 88 on gear 86 and bring about the rotation of the latter with results heretofore described.

Promptly upon the seam Ii in the cloth passing the bar 94 the latter returns to its normal position and switch I00 is again opened and solenoid I02 deenergized. Similarly when a piece of detected metal passes beyond the plates I26 and I28 the circuit through solenoid I02 is again opened. When this occurs-lever I03 will swing to the right and permit spring I20 to draw the latch bar H8 back against the switch lever I22, but with its latch I24 to the left side of lever I22, as seen inFigure 2.

The latch bar H8, however, is connected by a rod H0 with lever 88 and 'as the upper arm of the latter swings clockwise, it pulls the latch bar with it so that the latter swings about its pivotal mounting at I 23. This causes the latch I24, to slide across the switch lever I22 and eventually. by virtue of the pull of spring I20, to move to the right asseen in Figure 7 and in position to engage switch lever I22. Accordingly as the upper arm of lever 68 swings counterclockwise, the rod IIS pushes the latch bar H8 and with it the switch lever I 22 to the left as seen in Figure 2. This effect opening of switch H4 and deener- As a result armature II 0 drops bringing about the. disengagement of the clutch elements 88 and 90.

The cam 14 is so designed and rotated at a proper speed to effect the separation of the reseam detecting mechanism. Furthermore, even though I have used for illustration a machine having only one revolver, my invention may be applied to machines having more than one revolver. r

I claim as my invention: 1. In a machine for shearing surface threads from a strip of cloth, having a cloth rest and a rotary cutter between which the strip of cloth passes at the shearing position, electrically con- I trolled means for displacing the cloth and the rotary cutter relatively out of shearing relation to each other, comprising a device having terminal plates electrically insulated from one another, extending across the path of travel of the cloth, connected in the electrical circuit of said electrically controlled means and over which approximately the full breadth of the strip of cloth passes on its course to the shearing position, said extended plates being responsive to contact simultaneously with any piece of metal carried by the cloth for closing said electrical circuit, thereby" to cause relative displacement of the cloth and the rotary cutter at the shearing position.

2. In a machine for shearing surface threads from a strip of cloth, having a cloth rest and a rotary cutter between which the strip of cloth passes at the shearing position, electrically consaid electrically controlled means and over which approximately the full breadth of the strip of cloth passes on its course to the shearing position, said plate being responsive to contact simultaneously with any piece of metal carried by the cloth for closing said electrical'circuit, thereby to cause relative displacement of the cloth and the rotary cutter at the shearing position; and means for maintaining said displacement for a time interval predetermined to permit the piece of metal to pass the shearing position.

volver 54 from the cloth rest 20 before the piece of metal or the seam reaches the latter and to maintain this separation just long enough to enablethe seam or metal-to pas the rest and not make contact with the revolver.

Although I have shown both a metal detector I and a seam detector, it is to be understood that either may be used separately. More particularly,when any seam detector is present on an al- 3. In .a machine for shearing surface threads from a strip of cloth, having a cloth rest and a rotary cutter between which the strip of cloth passes at the shearing position, rotary cutter relatively out of shearing relation to each other,

\ comprising mechanism responsive to passagegof a piece of metal passing between said mechanism and said plates can cause operation of said electricalls' controlled means to effect relative displacement of the cloth and the rotary cutter at the shearing position.

4. In a machine for shearing surface threads from a strip of cloth, having a cloth rest and a rotary cutter between which the strip of cloth passes at the shearing position, a series of metal plate elements slightly spaced apart and insulated from each other and set edgewise beside the path of travel of the cloth at a location in advance of the shearing position; said plates alternately being electrically connected together to provide a positive set of plate contacts and a negative set of plate contacts extending approximately throughout the full breadth of the strip of cloth and in contact with which said cloth passes on its course to the shearing position, said sets of plates being connected in an open electric circuit which is olosable by a piece of metal carried by the cloth and bridging any two adjacent plates, and means responsive to a closing of said circuit for displacing the cloth and the rotary cutter relatively out of shearing relation to each other at the shearing position, and for maintaining the displacement for a predetermined time interval long enough to permit the piece of metal to pass the shearing position.

5. In a machine for shearing surface threads from a strip of cloth, having a cloth rest and a rotary cutter between which the strip of cloth passes at the shearing position, electrically re-' sponsive means for moving the rotary cutter out of shearing relation to the cloth, and a metal detecting device having terminal plates electrically insulated from one another and-electrically connected to said electrically responsive means, said plates extending across the entire'strip of cloth in the path of travel of the cloth to the shearing,

rotary cutter between which the cloth passes at the shearing position, means for detecting metal which may be carried by the cloth and for causin relative displacement of the cloth and rotary cutter out of shearing relation until the detected metal passes the shearing position, said means comprising a stack of metal plates spaced slightly apart, and having thin insulation between adjacent plates, said stack being set with aligned edges of the plates beside the path of travel of the cloth on its course to the shearing position, said plates being connected in an electric circuit with each adjacent pair of plates constituting respectively a positive and a negative terminal of a bank of gaps in said circuit, the bridging of any of which gaps by apiece of metal carried by the cloth will close ,said electric circuit, and means responsive to a closing of said circuit for displacing the cloth and rotary cutter relatively out of shearing relation.

7. A metal detecting attachment for cloth shearing machines, comprising a stack of metal plates clamped fiatwise together with edges of the plates aligned at one side of the stack; each said plate being insulated from adjacent plates by a thin sheet of insulation material, and adjacent plates throughout the stack being electrically connected to different ones of two terminals, and means for mounting the stack on a cloth shearing machine with the aligned edges of the plates close beside and transversely of the path of travel of the cloth to the shearing position.

WILLIE LEO LAFOND. 

